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1.
Abstract

A survey of users of geosciences data in Great Britain, carried out as part of the Databank Pilot Study jointly supported by the Department of the Environment and the British Geological Survey, indicated a priority requirement for a central geosciences data index. The consultations suggested that the system should contain information about the sources, accessibility and nature of data held in both centralized and widely-distributed collections. To illustrate to users how such a system would appear in its final implementation, and in order to refine the system's specification, the British Geological Survey developed, on an Intergraph Interpro 32 Workstation, a working demonstration of a ‘user-friendly’, interactive graphical index, capable of satisfying the requirements of a wide range of users of geosciences data. This paper describes the development of the ‘demonstrator’, its structure, content and implementation, and the benefits of adopting such an approach.  相似文献   

2.
Lane-based road network information, such as lane geometry, destination, lane changing, and turning information, is important in vehicle navigation, driving assistance system, and autonomous driving. Such information, when available, is mainly input manually. However, manual methods for creating and updating data are not only costly but also time-consuming, labor-intensive, and prone to long delays. This paper proposes a hierarchical polygonization method for automatic generation and updating of lane-level road network data for navigation from a road marking database that is managed by government transport department created by digitizing or extraction from aerial images. The proposed method extends the hierarchy of a road structure from ‘road–carriageway–lane’ to ‘road–carriageway–lane–basic lane’. Basic lane polygons are constructed from longitudinal road markings, and their associated navigational attributes, such as turning information and speed limit, are obtained from transverse road markings by a feature-in-polygon overlay approach. A hierarchical road network model and detailed algorithms are also illustrated in this paper. The proposed method can accelerate the process of generating and updating lane-level navigation information and can be an important component of a road marking information system for road management.  相似文献   

3.
Abstract

This paper provides a brief survey of the history, structure and functions of ‘traditional’ geographic information systems (GIS), and then suggests a set of requirements that large-scale GIS should satisfy, together with a set of principles for their satisfaction. These principles, which include the systematic application of techniques from several sub-fields of computer science to the design and implementation of GIS and the integration of techniques from computer vision and image processing into standard GIS technology, are discussed in some detail. In particular, the paper provides a detailed discussion of questions relating to appropriate data models, data structures and computational procedures for the efficient storage, retrieval and analysis of spatially-indexed data.  相似文献   

4.
Abstract

The CORINE programme (Co-ordinaled' Information on the European Environment) has been underway since 1985. Its purpose is to provide information on the environment of the entire European Community in a form suitable for assisting policy making. Such data must be accurate, integrated and readily available to the personnel for whom the system is designed. The system must be capable of dealing with large amounts of spatially-linked data from many different sources, in text, vector or raster form. The use of a geographic information system (GIS) is therefore essential. This paper describes the use of an interim system as a ‘bed’ for beginning the process of acquiring and integrating data. The data sets available are soils, climate, topography and ‘biotopes) (important areas for nature conservation). A data transfer format has been devised to provide for ease of transfer between various sites in the European Community with different mainframe computers. The interim system ensures that the needs of users can be defined and provides valuable user experience before a permanent system is installed. Other issues examined include the use of national and international networks and problems of integrating data when incorporating existing digital data from disparate sources into a large GIS.  相似文献   

5.
Abstract

Remotely-sensed data constitute a major potential source of input to geographical information systems (GIS)However, these data often have a relatively poor classification accuracy compared with that of the cartographic data from maps with which they may be combined in the course of GIS analysis. The possibility exists of using data sets (in the form of digital maps) resident within a GIS in order to improve this accuracy, before the classified image is incorporated into the GIS. Results are discussed from a British Alvey Information Technology project to develop a system for the knowledge-based segmentation and classification of remotely-sensed terrain images, in which the knowledge contained in digital map  相似文献   

6.
Abstract

Databases used in geographical information systems must be supplied with current data. Maps are usually out of date when they are published. Satellite imagery and aerial photographs supply up-to-date three-dimensional data. Three different models for real-time quality assurance control in three-dimensional data collection for geographical information systems are discussed. Emphasis is placed on the visual detection of ‘blunders’ in three-dimensional data. One data collection quality assurance model has been implemented in the Photogrammetric Analysis Laboratory at Purdue University. An example from this system is given and the precision and speed of digitization of three-dimensional data are discussed.  相似文献   

7.
Abstract

This paper describes an inductive modelling procedure integrated with a geographical information system for analysis of pattern within spatial data. The aim of the modelling procedure is to predict the distribution within one data set by combining a number of other data sets. Data set combination is carried out using Bayes’ theorem. Inputs to the theorem, in the form of conditional probabilities, are derived from an inductive learning process in which attributes of the data set to be modelled are compared with attributes of a variety of predictor data sets. This process is carried out on random subsets of the data to generate error bounds on inputs for analysis of error propagation associated with the use of Bayes’ theorem to combine data sets in the GIS. The statistical significance of model inputs is calculated as part of the inductive learning process. Use of the modelling procedure is illustrated through the analysis of the winter habitat relationships of red deer in Grampian Region, north-east Scotland. The distribution of red deer in Deer Management Group areas in Gordon and in Kincardine and Deeside Districts is used to develop a model which predicts the distribution throughout Grampian Region; this is tested against red deer distribution in Moray District. Habitat data sets used for constructing the model are accumulated frost and altitude, obtained from maps, and land cover, derived from satellite imagery. Errors resulting from the use of Bayes’ theorem to combine data sets within the GIS and introduced in generalizing output from 50 m pixel to 1 km grid squares resolution are analysed and presented in a series of maps. This analysis of error trains is an integral part of the implemented analytical procedure and provides support to the interpretation of the results of modelling. Potential applications of the modelling procedure are discussed.  相似文献   

8.
Abstract

The Institute of Terrestrial Ecology (ITE) Digital Cartographic Service provides a range of services to the scientists of ITE (and others) including various techniques within the field of geographical information systems (GIS). This paper discusses work of this type as it is applied to specific ITE projects. The emphasis is very much on GIS applications to ‘real ecological science’ such as the ‘acid water’ problem and the change of forest areas into heathland. Some comments are made on fundamental GIS techniques, their use and limitations. At ITE, GIS applications are growing out of an existing use of digital mapping and remote sensing technologies; they have not purchased a GIS system ‘off the shelf.’  相似文献   

9.
Abstract

This paper is a case study of issues that have frustrated and slowed the development of a geographical information system for automation of topographic information processing within the U.S. Army. The findings, which are universal to all large organizations attempting to develop an initial capability, reinforce the notion that today most problems in the development of geographical information systems are rooted in organizational rather than technological issues. An iterative prototyping approach is suggested as a means of preventing similar situations when introducing such technology into large organizations. This ‘hands-on’ approach allows the organization and the people to adopt and evolve in parallel with the technology and improves the chances for success.  相似文献   

10.
11.
Abstract

Digitizing still remains a major bottle-neck in the creation of geographical data bases. This paper examines procedures and equipment used in the Dane County Land Records Project as a tutorial for others interested in digitizing maps. Topological structure, determined from ‘spaghetti and meatballs’, detects the important errors and provides a basis for efficiency (in time and cost). For manual digitizing, a simple system of capture running on cheap hardware may be as effective as an expensive workstation. Scanning technology, which used to be expensive, has now become practical, as is shown by an experimental scanner used in this project.  相似文献   

12.
Providing an introduction to the special section ‘Close encounters: ethnographies of the coproduction of space by the urban poor’, this article sets out to argue that the image of ‘the informal’ as unruly, messy and dirty continues to inform urban planning around the world. As a reaction to this view, it contends that the informal and formal should be analysed as interconnected and that the informal sphere should be revalued. Urban development is studied as close encounters between established practices, with a locus and a history (tree‐like), and newly emerging, unstable and untraceable practices (rhizomatic). Contrary to the tendency in urban planning to conflate the formal with the tree and the informal with the rhizome, we argue that from the perspective of marginal urbanites, formal planning tends to be very arbitrary and frightening (rhizomatic), whereas informal practices can be very predictable and stable (arboreal). The article analyses residents of marginalized urban areas as inventive navigators who explore the changing physical, spatial and sociopolitical environment, avoiding threats and looking for opportunities, grounded in their everyday practices and life histories. The article concludes that marginal urbanites should be acknowledged as coproducers of urban space and that the right to ‘coproduce’ the city lies at the heart of the call for the right to the city.  相似文献   

13.
Abstract

Appropriate technology (AT) has become an integral part of the programmes for decentralized regional development in the Third World. ‘Appropriate’ techniques are usually low in capital costs; they can be maintained without a high level of expertise; and they do not involve patents, expensive copyrights and royalties. By these criteria a commercial geographical information system (GIS) is not an appropriate technology to be used in decentralized development However, the use of local renewable resources involves the adoption of end-use analysis for matching end-uses to specific sources so as to minimize the consumption of material and energy (i.e., minimize entropy). This matching requires much information which leads to what may be called the 'information-entropy trade-off; minimization of entropy requires an inverse increase in information. In this respect computers and GIS have an important contribution to make to decentralized regional planning. Drawing on a case study in Sri Lanka, this paper presents some ideas on how to incorporate GIS into local-level planning information systems.  相似文献   

14.
New sources of data such as ‘big data’ and computational analytics have stimulated innovative pedestrian oriented research. Current studies, however, are still limited and subjective with regard to the use of Google Street View and other online sources for environment audits or pedestrian counts because of the manual information extraction and compilation, especially for large areas. This study aims to provide future research an alternative method to conduct large scale data collection more consistently and objectively on pedestrian counts and possibly for environment audits and stimulate discussion of the use of ‘big data’ and recent computational advances for planning and design. We explore and report information needed to automatically download and assemble Google Street View images, as well as other image parameters for a wide range of analysis and visualization, and explore extracting pedestrian count data based on these images using machine vision and learning technology. The reliability tests results based on pedestrian information collected from over 200 street segments in Buffalo, NY, Washington, D.C., and Boston, MA respectively suggested that the image detection method used in this study are capable of determining the presence of pedestrian with a reasonable level of accuracy. The limitation and potential improvement of the proposed method is also discussed.  相似文献   

15.
16.
《The Journal of geography》2012,111(6):236-244
Abstract

Field trips have been acknowledged as valuable learning experiences in geography. This article uses Kolb’s (1984) experiential learning model to discuss how students learn and how field trips can help enhance learning. Using Kolb’s experiential learning theory as a guide in the design of field trips helps ensure that field trips contribute to internalizing relevant geographical theory and concepts. Three types of field trips are presented: an informal survey of a neighborhood, a more formal scavenger hunt, and a virtual field trip using Google Earth.

Learning is the process whereby knowledge is created through the transformation of experience.

—Kolb (1984)  相似文献   

17.
ABSTRACT

Indigenous public artworks in Australian urban spaces have challenged assumptions of Indigenous absence from the city. This paper examines the construction of Birrarung Wilam, in central Melbourne, in the period 2005–2008. We use archival documents and semi-structured interviews to analyse the collaborations between Indigenous and non-Indigenous participants in a project sponsored by the city. We show the particular mediating contribution of ‘fabricators’: a group of commissioned workers and tradespeople with material-specific expertise. Person to person encounters occurred through the modules of project management, with limited scope for long-term engagement. Despite being embedded in formal state-based recognition, Birrarung Wilam asserts Indigenous self-recognition through the renewal and adaptation of Indigenous material practices and traditions and the refusal to provide straightforward interpretive materials at the site. The study provides support for arguments that challenge a simple binary of co-option and resistance in interpreting such public art practice.  相似文献   

18.
ABSTRACT

Cellular automata (CA) models are in growing use for land-use change simulation and future scenario prediction. It is necessary to conduct model assessment that reports the quality of simulation results and how well the models reproduce reliable spatial patterns. Here, we review 347 CA articles published during 1999–2018 identified by a Scholar Google search using ‘cellular automata’, ‘land’ and ‘urban’ as keywords. Our review demonstrates that, during the past two decades, 89% of the publications include model assessment related to dataset, procedure and result using more than ten different methods. Among all methods, cell-by-cell comparison and landscape analysis were most frequently applied in the CA model assessment; specifically, overall accuracy and standard Kappa coefficient respectively rank first and second among all metrics. The end-state assessment is often criticized by modelers because it cannot adequately reflect the modeling ability of CA models. We provide five suggestions to the method selection, aiming to offer a background framework for future method choices as well as urging to focus on the assessment of input data and error propagation, procedure, quantitative and spatial change, and the impact of driving factors.  相似文献   

19.
Abstract

A simple, exemplary system is described that performs reasoning about the spatial relationships between members of a set of spatial objects. The main problem of interest is to make sound and complete inferences about the set of all spatial relationships that hold between the objects, given prior information about a subset of the relationships. The spatial inferences are formalized within the framework of relation algebra and procedurally implemented in terms of constraint satisfaction procedures. Although the approach is general, the particular example employs a new ‘complete’ set of topological relationships that have been published elsewhere. In particular, a relation algebra for these topological relations is developed and a computational implementation of this algebra is described. Systems with such reasoning capabilities have many applications in geographical analysis and could be usefully incorporated into geographical information systems and related systems.  相似文献   

20.
Abstract

Abstract. The growth of the remote sensing field has caused and explosion in the size and complexity of Earth satellite image databases. The explosion of data is already challenging current satellite-based GIS databases. New technologies for information management will be required in the future to maintain these large geographically-oriented systems created by projects such as NASA's Earth Observing System (EOS). This paper presents a technology adapted from the planning/scheduling field in Artificial Intelligence (AI) that promises to automate and facilitate the process of creating and storing satellite images and their associated data products.  相似文献   

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